LEADING CLIMATE change experts have warned of the "Hollywoodisation" of global warning and criticised American scientists for exaggerating the message of global warming.

Paul Hardaker and Chris Collier of the U.K.'s Royal Meteorological Society said scientists, campaign groups, politicians, and the media were all guilty of making out that catastrophic events were more likely to happen when this could not be proved by scientists. They also criticised the tendency to say individual extreme events — such as a typhoon or floods — were certain evidence of climate change.

They singled out for criticism a report last month by the American Association for the Advancement of Science, which said intensification of droughts, heat waves, floods, wildfires and storms were "early warning signs of even more devastating damage to come."

"It's certainly a very strong statement," said Professor Collier. "To make the blanket assumption that all extreme weather events are increasing is a bit too early yet."

Media criticised

Reporting of the recent report by the United Nations International Panel on Climate Change by the media was also criticised, especially the use of words not in the report such as "catastrophic," "shocking," 'terrifying," and "devastating."

"Campaigners, media, and some scientists seem to be appealing to fear in order to generate a sense of urgency," said Mike Hulme, director of the Tyndall Centre for Climate Change Research at the University of East Anglia.

The report by Professors Hardaker and Collier, and other climate experts, "Making Sense of the Weather and Climate," was launched at a conference in Oxford, England, organised by the charity Sense About Science. The authors said they firmly believe global warming is happening and man-made emissions of greenhouse gases are partly to blame.

Some scientists also acknowledged that dramatic warnings about climate change had helped generate public debate and support for action to reduce the threat. But Professor Hardaker warned that exaggeration of the problems made the public confused and made it easier for sceptics to argue that the scientists were wrong.

An example of a low probability event given too much weight was the risk of the Gulf Stream, which keeps the North Atlantic relatively warm, "switching off" and plunging the region into an ice age — the scenario dramatised by the Hollywood film The Day After Tomorrow, which also came in for criticism for exaggerating that problem. As a result scientists had to be more honest about the uncertainties surrounding climate change prediction to avoid losing public trust, said Professor Hardaker.

"Once you begin to exaggerate the science in either direction the debate gets out of control," he said. Their comments were backed today by other leading figures in the debate.